Re: [Exim] MySQL persistant?

Philip Hazel wrote:
>> Well, I'd like to note, that I'd love to see exim caching a few
>> more MySQL queries/results, as just one single query cache is to
>> less in many setups. Anyone into making the cache an array instead
>> of a simple scalar?
>
> Given Exim's short-lived process model, I don't think that you would
> gain too much by doing that.

Well, this depends on how many MySQL requests are needed for one
delivery. Given my setup, it could require more than 10 (up to about 15)
queries per delivery, verification not included. (Cause this is done in
a different process...) I got them down to 3 - 5 per delivery by
combining different options into one clumn, but that's not quite perfect.

One major point I first wondered about, was that my domainlist
local_domains is expanded to the mysql query each time it is used. It
would be sufficient - at least or my setup - if a domainlist could cache
it's own result. (I know, it _does_ if it is sure to expand to the same
result each time, but I'd like it to cache for DB queries / file lookups
too.. Maybe a "static" or "once" option for lists could be added as a
new feature in future?)

> There was a suggestion of writing a permanently-running "database
> query and caching engine" which could be accessed via a socket.

I'm not sure whether this would give much improvement compared to a
MySQL engine accesed via a local socket. Might be much work for
relatively less benefit... (It may be a good idea for setups with remote
DB Servers, though.)

> But somebody needs to implement it...

As always...


lg,
daniel